They'll just claim the oil is enhanced with Miracle Ingredient Pu-244, for better engine performance and faster starts during cold weather. :P
(Seriously speaking, most of the oil is hundreds to thousands of feet deep; even a bunker-buster nuke isn't going to do much to the oil, one way or another.)
Re: "D'oh"
(Seriously speaking, most of the oil is hundreds to thousands of feet deep; even a bunker-buster nuke isn't going to do much to the oil, one way or another.)